F39: Failure of Success Criterion 1.1.1 due to providing a text alternative that is not null (e.g., alt="spacer" or alt="image") for images that should be ignored by assistive technology

Applicability

Description

This technique describes a failure condition for images that should
be ignored by assistive technologies. A text alternative for an image
should convey the meaning of the image. When an image is used for decoration,
spacing or other purpose that is not part of the meaningful content
in the page then the image has no meaning and should be ignored by
assistive technologies.

Providing a null text alternative (i.e., alt="" or alt=" ")
will allow assistive technology to ignore the image and avoid a failure
of this Success Criterion.

Note: Although alt=" " is valid, alt="" is
recommended.

Examples

Example 1: Decorative images that have no alt attribute

An image is used to create a blank space between content, where the
spacing itself is not meaningful to the content. The image has an alt
text value of "spacer". This image fails the Success Criterion
because the text alternative does not serve an equivalent purpose.
The image is meant to be ignored but its alternative text "spacer" is
announced by screen readers and displayed in some alternate color schemes.